Cooking and frying oil compositions typically comprise vegetable oil-based triglycerides. However, the relative hydrolytic instability of triglyceride molecules diminishes the fry life of such oils, resulting in the need for more frequent change intervals. Synthetic estolide compounds present a hydrolytically-stable alternative to triglycerides that may be useful in extending the fry life of cooking oil compositions. Frying/cooking food articles with estolides may also provide consumers with a healthier alternative to triglyceride-based oils.